Embodiments of the present invention relate to a semiconductor device having a line-type active region, and more particularly, to a semiconductor device where the width of an isolation gate for device isolation in the line-type active region is different from the width of an active gate so as to guarantee a wide storage node contact region, thereby improving device operation characteristics (write characteristics).
As is well known in the art, a semiconductor device, such as a DRAM, must have a small unit cell size to reach a higher degree of integration.
However, as the cell transistor becomes smaller in size, the driving current is reduced and the leakage current is increased due to the short channel effect. A buried gate structure based on a metal gate has been proposed to reduce the leakage current while increasing the integration degree of the cell transistor. In addition, a method for forming a line-type active region along with a buried gate and a method for isolating an active region using an isolation gate have been intensively studied.
However, as a semiconductor device that has a line-type active region is gradually decreased in size, the storage node contact area of the semiconductor device is gradually reduced as well, resulting in deterioration of write characteristics of cell operation.